天然胶体的水环境行为

胶体是一种分散相粒子具有特定粒径(通常为1 nm~1μm)的混合物,天然水体中的胶体通常是指水环境中普遍存在,而又符合“胶体”形态定义的物质的总和.因为具有特殊的表面性质以及独特的水动力学特点,天然水体中的胶体被认为是一种重要的污染物载体,尤其在促进重金属类的污染物迁移以及性质转化的过程中具有重要作用.本文归纳总结了水环境研究领域中胶体概念的提出与发展,讨论了现有研究中对胶体的定义与理解,比较了当前几种主要的胶体提取手段的特点.同时,针对胶体在水环境中的环境行为,详细归纳了河湖水体中胶体的物质组成、特征以及相应的检测手段,重点总结了胶体在水环境中对污染物的结合作用、胶体污染物的生物效应、胶体自身的团聚规律以及胶体对污染物迁移的影响机制.本文提出了胶体在水环境中复杂的组成成分与动态变化在胶体研究中的重要性,并对进一步揭示胶体环境效应的研究思路以及方法手段进行了展望.

Environmental behaviors of natural colloids in water environment

Colloid is a mixed multi particle system with particle diameters between 1 nm and 1μm.The natural aquatic colloids are defined as the sum of the ubiquitous substances in the aquatic environment with"colloidal"form.Due to the specific surface chemistry and long residence time in the environment,colloids play an important role in regulating the speciation,transformation,and fate of trace metals and other pollutions.In this paper,the formation and development of colloids in the research field of water environment were summarized and concluded,and the definition and separation method of natural aquatic colloids were discussed and compared.To better understand the environmental behaviors in water environment,the characteristics,composition of natural aquatic colloids,and the corresponding detection method were summarized in detail.This paper also summarized and concluded the major research findings about the binding interaction between colloids and pollutants,the migration and aggregation of colloids,and its impacts on the transportation and transformation of pollutants.Finally,this paper emphasized that the complex composition and dynamic processes of colloids are innovative to the research of colloids in water environment,and the research methods and thoughts have been outlook for further study on the environmental effects of colloids.